DR-M4

Refractive index or Abbe number ( ?d or ?e ) can be measured at different wavelengths ranging from 450 to 1,100nm ( For measurement at wavelengths ranging from 681 to 1,100nm, the Optional Near Infrared Ray Viewer ( RE-9115 ) is required. ) The DR-M4 displays measurement result of refractive index or Abbe number digitally on the LCD. Measurement can be achieved by matching the boundary line with the intersection point of the cross hairs. This refractometer is connectable with Digital printer DP-21 ( A ) ( Optional ) .